The basic principle of matza is time. There is no way of getting leavened bread without time by definition. So in short, oatmeal or wheat flour it can not become leaven without time. Thus you could put oatmeal into a pot and cook it, and it can not become leaven. Same with wheat.
And after it has gotten to be cooked, it also can not become leaven. [So you can have the regular breakfast of hot oatmeal that some people are used to. Not only can oatmeal not become hametz unless it sits in water for over 18 minutes but after it is cooked it can never become hametz ever even after a million years.]
To make you own matza to say a blessing on is simple. Get a frying pan. The only thing is if you mix wheat flour and water to make maza to say the hagada, then there is this issue. If the mix flows like a pancake, then it is not bread but cake. To say the blessing, "Who brings forth bread" it has to be thick enough that it does not flow.
[This can be hard to decide. What if it flows a little, but not like a pancake?]
And after it has gotten to be cooked, it also can not become leaven. [So you can have the regular breakfast of hot oatmeal that some people are used to. Not only can oatmeal not become hametz unless it sits in water for over 18 minutes but after it is cooked it can never become hametz ever even after a million years.]
To make you own matza to say a blessing on is simple. Get a frying pan. The only thing is if you mix wheat flour and water to make maza to say the hagada, then there is this issue. If the mix flows like a pancake, then it is not bread but cake. To say the blessing, "Who brings forth bread" it has to be thick enough that it does not flow.
[This can be hard to decide. What if it flows a little, but not like a pancake?]